Crystal structure of fulvestrant hydrate (ethyl acetate), C32H47F5O3S(H2O)0.16(C4H8O2)0.025

Abstract

The crystal structure of fulvestrant hydrate (ethyl acetate) has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. This solvate of fulvestrant crystallizes in space group R3 (#146) with a = 23.39188(16), c = 16.50885(13) Å, V = 7823.08(7) Å3, and Z = 9. The crystal structure is composed of triangular hydrogen-bonded chains of molecules around one of the threefold axes. The fluorinated ends of the molecules cluster around another threefold axis. Voids around a threefold axis occupy 8.1% of the unit cell volume, and are partially occupied by the water and ethyl acetate molecules. Both hydroxyl groups act as donors in O–H⋯O hydrogen bonds. These H-bonds form a large ring. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).